I’m looking for an sleek integrated amp under $15k

Aavik I-280, was paired with Vivid Kaya 45s, absolutely magical pairing.....believe the Aavik was around $12,000. I would definitely audition if I could find a dealer near me.....believe they have 11 or 12 dealers in the US.

The all sound very different so it's really better to get out to hi-fi shops and test combinations with the speakers that you want to use.  That's half the fun.  With your budget you can consider separates.

Pass Labs INT-60

I have owned my McIntosh MA12000 almost 2 yrs now (also have a Hegel in my den). Listen to and auditioned several others in the same price point. The MA12000 is my last - and will be passed on to my kids. It was a financial stretch for me personally, but after two yrs - the best audio purchase I have made. It does everything well, very well, some exceptionally. The tube preamp side I would offer as much more than exceptional as is the connectivity for anything and everything. Built like a tank, future proof DAC/card system...currently their 2nd gen DAC. Some of the newer MC products I have listened to = more decorative than functional...but the MA12000 will be an iconic hallmark, one that Mc Labs has ever made.  Audio Excellence Canada has an in-depth review on U-tube